It was a foggy afternoon on 15 December, 1944 when the Norseman aircraft carrying Glenn Miller flew close to Maidenhead, Berkshire.

Soon after it would be seen for the last time at Beachy Head in East Sussex.

What happened next to the craft and its famous passenger, who led the World War II big band craze, has never been uncovered.

No sign of the aircraft was ever found and Miller's disappearance remains one of World War II's most enduring mysteries.

And until now, it had never been confirmed the route the aircraft had taken saw it travel by Maidenhead.

The band leader and jazz trombonist, famous for records including Pennsylvania 6-5000 and In The Mood, was on his way from Bedfordshire to entertain US troops in Versailles, France - a flight which should have taken him across the English Channel.

Image caption
Sylvan Anderton, 77, said he had kept his brother's plane-spotter notebooks for 28 years

His UC-64A Norseman, an American transport aircraft, never arrived. No trace of the aircrew, passengers or plane has ever been found.

Varying theories about different flight paths have abounded, but the Berkshire route has now been confirmed by the Glenn Miller Archive at Colorado University, and will feature as one of the facts in an official report on the musician's disappearance, commissioned by Glenn Miller's children.

The most recent discovery started with a 17-year-old plane-spotter in 1944, who meticulously logged each plane he saw flying overhead while he worked at an airfield in Woodley, Reading.

The now deceased Richard Anderton had two small notebooks filled with details of the locations of passing aircraft, estimated altitude and directions of flight.

'Pinch of salt'

On 15 December 1944, he logged a UC-64A-type aircraft passing on the horizon to his east and flying below the fog in a south-easterly direction.

"If I had £10 for every time I heard someone with a new bit of information on Glenn Miller I'd have bought my own Caribbean island by now"Dennis Spragg, Glenn Miller Archive

It was not until his brother, 77-year-old Sylvan Anderton, brought the books into the BBC's Antiques Roadshow TV programme 67 years later that the entry came to light.

"I'd had them for about 28 years and really didn't do anything about it," said Mr Anderton, who grew up in Reading but now lives in Bideford, Devon.

"I knew there was a connection because he'd cut out an article from the Daily Express in 1969 about Glenn Miller's disappearance and he'd put it in the pages in the notebook for 15 December 1944."

Roadshow expert Clive Stewart-Lockhart, who valued the books at around £1,000, said Glenn Miller was "one of the great mysteries of that part of the war," and that he found the teenager's dedication to plane-spotting extraordinary "when a bomb could've dropped on him".

He has never questioned the authenticity of the notebooks.

"You'd have to be an absolute genius to make it up," he said.

'Very valuable'

But when it came to official verification, Dennis Spragg, senior consultant at the Glenn Miller Archives in Colorado, said he initially took the notebook entry "with a pinch of salt".

"I was a bit sceptical," he said.

"If I had £10 for every time I heard someone with a new bit of information on Glenn Miller I'd have bought my own Caribbean island by now."

But when he looked into it, and found out Mr Anderton was based at Woodley - within eight miles of the Maidenhead waypoint - pieces of the puzzle started to fit.

Image caption
The entry for 15 December, 1944 notes a Norseman, the only such aircraft flying that day

Mr Spragg said if the craft was passing to the east of Mr Anderton, he indeed would have been able to have seen it on his horizon.

"I went back and consulted the records for what would've been the route of the flight," he said.

"I worked out flight times and the speed of the aircraft and worked out that he probably saw the airplane to his east at eight or nine minutes past two in the afternoon."

He said the discovery was "very valuable".

"It's a piece of the entire story. The notebook confirms that the plane was on time and on course."

It also eradicates other theories about alternate routes the plane could have taken.

"All the speculators saying he went east of London have now gone out the picture," said Mr Anderton.

Aside from the notebook's historic significance, his late brother's unexpected new status as the next-to-last known observer of Glenn Miller's plane has caused some excitement in the Anderton household.

"We're part of the Glenn Miller story, we're very thrilled about that," he said.

"We've even started playing his music."

The notebook entry will feature in Dennis Spragg's report called Major A Glenn Miller, 15 December 1944, The Facts, which is due to be published this year.